Danny Fox said Nottingham Forest didn’t reach the levels they can do in the defeat against Millwall yesterday.
The defender was left frustrated at the performance and the defeat which left Forest six points adrift of the play-off positions.
Speaking after the game, he said: "It was frustrating as we knew exactly what we were coming into. To not perform to the level we have done this season was really annoying.
"They make it hard and the fans as well, everyone plays their part here. They get onto the referee and the linesmen but we get paid to deal with that and we didn't deal with it today.
"We had a lot of the ball and when we got into the final third I don't think we created as much as we would have liked to."
The defeat was just The Reds' second on the road this season but it extended a winless run to five games and Fox knows that they need to start winning games if they are to keep in the promotion hunt.
He said: "It is disappointing, especially after Norwich on Boxing Day as nobody wants to lose any games of football.
"I said to the boys in the changing room that we are missing out on a great opportunity. Obviously our aim is promotion and to go up but if we don't start performing then we will be nowhere near it.
"We need to start winning and it is down to myself, the team and everyone associated with the club."